Computational modeling of creep-based fatigue as a means of selecting lead-free solder alloys

•The creep behavior of lead free solders was successfully simulated for all models.•Corners and interfaces are the areas where solders experience the max. stresses.•Power cycles develop a higher strain in the joints in comparison with thermal cycles.•Parameterization study showed the effect of solder thickness on joint reliability. The primary aim of this investigation was to understand the effect of temperature fluctuations on a number of various solder materials namely SAC105, SAC305, SAC405 and Sn–36Pb–2Ag. To achieve this objective, three different classic joint assemblies (a ball joint, a test specimen joint and finger lead joint) were modeled which provided the foundation for the creep and fatigue behaviors simulation. Anand’s viscoplasticity as a constitutive equation was employed to characterize the behavior of solders numerically under the influence of thermal power cycles (80–150°C) and thermal shock cycles (−40 to 125°C). To extend the research outcome for industrial use, two additional research activities were carried out. One of them was to obtain lifetime-predictions of solder joints based on Coffin Manson concept. The other one focused on parameterization to obtain the ideal solder thickness under the consideration of plastic strain and economic benefit.